Development of Procedure for Stage C Commissioning: Reactor Performance Test (LOEP) for a Research Reactor

The procedures may also be used as an aid for assessing and documenting the results of tests. The commissioning procedures should include information that specifies several items. Those are mainly (1) all the activities and performance parameters that are to be measured under specified steady state and transient conditions, (2) the requirements on performance, together with clearly stated acceptance criteria. The final phase of stage C commissioning is reactor performance test, which is to prove the integrated performance (neutron power calibration, Control Absorber Rod drop time, I and C functioning, Rod worth, Core heat removal with natural mechanism) and the safety of the research reactor at full power with fuel loaded. Commissioning procedure was developed to show the safety of the research reactor. Both indirect and direct indicators were selected to show that the safety is ensured: 1) indirect parameters which imply success of safety functions: power, flow, opening valves, system response as-designed; 2) direct parameters which shows no failure of safety functions: no meaningful increase in level of neutron in the cooling system. Preliminary analyses have shown all probable thermal-hydraulic transient behavior of importance as to opening of flap valve, minimum critical heat flux ratio, the change of flow direction, and important values of thermal-hydraulic parameters. A preliminary comparison to conservative estimation has shown that the nuclear reactor safety of the research reactor will be assured by verifying that the reactor power and the PCS flow rate are conservative